One of the most popular claims concerns the depiction of Muller as some kind of “reformed skeptic”, some pretty soul who’s finally seen the data, and the light alongside. Here’s the UK’s Independent repeating the party line, for example.

Professor Richard Muller, a physicist at the University of California, Berkeley, who has been an outspoken critic of the science underpinning global warming, said that there is little doubt in his mind the phenomenon of rising land temperatures is real.

back in the early ’80s, I resigned from the Sierra Club over the issue of global warming. At that time, they were opposing nuclear power. What I wrote them in my letter of resignation was that, if you oppose nuclear power, the U.S. will become much more heavily dependent on fossil fuels, and that this is a pollutant to the atmosphere that is very likely to lead to global warming

Well, I can now report (with no worry of being refuted) that Richard Muller has been a climate skeptic all along. And he has not. At the same time!

The important point, in fact, is the definition of “climate skeptic”.

In a saner world, a “climate skeptic” would simply be any person approaching the field of climate change with a critical eye, and especially about the more outlandish claims of impending catastrophes caused by humans burning “fossil fuels” and doing all the other nasty things humans do. Of course, in a saner world 99.999% of the people would be “climate skeptic” and there would be little or no discussion about “global warming” or “climate change” being the “the world’s greatest challenge“.

From the sane point of view then, Muller, a guy who resigned decades ago about the “global warming” issue and believes humans are quite likely causing it, is no skeptic at all. From Muller’s own “Physics for Future Presidents” (chapter 10, page 18):

Humans have very likely contributed to global warming, and that suggests that
the worst effects are still ahead of us.

Coming back instead to the insane world we live in, definitions change. In particular, in the eyes of AGW True Believers a “climate skeptic” (aka “climate denier”) becomes anybody that questions anything about the IPCC-led climate change orthodoxy. And by that I mean, anything. It doesn’t matter if one surmises the world has been warming (the very definition of “global warming”), and that humans are “very likely” causing that (the very definition of “anthropogenic global warming”): all it takes is an expression of uncertainty or doubt about whatever topic, and immediately the brainless hordes will descend in full fascistic gear.

In fact, much of what you hear every day is exaggerated, often on purpose.
People feel so passionately about climate change, and they are so frightened about
what is coming, that they overstate their case (either pro or anti) in an attempt to
enlist proselytes

All in all, it looks like nobody knows who Richard Muller actually is. Expect surprises.

It is fascinating how just questioning one part of the IPCC narrative lands you in trouble with the “true believers”. How anyone can call this science I really have no idea. If the IPCC hasn’t been created, perhaps by now we might actually know the reality of how the climate works and the influences upon it. All we’ve got instead is a singular focus on CO2, and any other forcings are mostly ignored.

that hockey-stick would have a very strange shaft! The 95% confidence limit would range from -278 -to about +50 degC. It would be a fair bet that the actual temperature was somewhere in there. Are you expecting an onslaught from the Team? It seems that Steig spotted the problem before Tamino….you can imagine them huddled in a bunker somehere in the Appalachians, working on their strategy and begging Romm to bluster about Koch-funded Muller in his painfully asinine way.

actually, I think the Team is looking at the start of the time series graph and seeing what a problem it creates for them. They need to kick this reconstruction into the long grass as fast as possible.

If you take the uncertainy limits in say 1810, then the worls has probabloy warmed between 1.5 – 2.5 deg C in the course of 200 years. If Briggs and Keena are correct that the uncertainty is understated, then it could be a range between ! – 3 deg C – just from eyeballing.

This obviously makes a mockery of the claims of disaster if the world warms by 2 deg C or whatever arbitrary number they plucked out of the air for the IPCC.

Similarly, if you look at 1820 and extend the error range, then it is not so much cooler than the current temperature, which destroys the claim that the world today is unprecedentedly warm. Taking this further, in the light of this total uncertainty over the temperature 200 years ago, if this is the best we can do with thermometers – instruments designed to measure temperature – how much reliance can we place on lake sediments, tree-rings, stalactites, ice cores etc.? If thermometers do not give an answer, how can we trust the proxies to give us more than a vague qualitative hint as to the past temperature?

Maurizio, apologies if you’ve seen this before but this special from UNESCO in 1973 (building on the United Nations Conference on the Human Environment in Stockholm, June 1972). I’ve seen Limits to Growth before but not Only One Earth.

My take is that Muller is a longtime CAGW apologist who recognized the harm done to his cause by the obvious fraud of The Hockey Stick and set about to attempt to restore some measure of credibility to the CAGW meme by constructing an alternative temperature record sans Hockey Stick.

I have to applaud Muller for exposing The Hockey Stick. He demonstrated integrity in doing so. How deep and wide that integrity runs is yet to be determined.